1. Product Overview The MR104ZZ miniature ball bearing is designed for micro precision rotary equipment, offering low friction, dust resistance and ultra-high rotational stability.It is widely used in 3C electronics, drone motors, optical instruments and miniature medical devices where limited installation space and quiet high-speed operation are required. 👉 Get a quote within 24 hours for your project 2. Technical Specifications Model: MR104ZZ Inner Diameter (ID): 4mm Outer